What is the Remove Duplicate Lines tool?
Duplicate lines creep into every list that grows over time: keyword exports, email subscriber lists, product SKUs, log files, and survey answers. This free tool scans your list line by line, keeps one copy of each unique line, and drops the rest — in seconds, without sending your data anywhere.
How to use it
- Paste your list into the box on the left, one item per line.
- Choose your options: ignore case, trim whitespace, remove empty lines, or sort the result.
- The clean list updates live on the right. Copy it, or download it as a .txt file.
Who uses it?
- SEO specialists — deduplicate keyword lists before importing them into rank trackers. See the SEO workflow.
- Marketers — clean email lists so subscribers are never mailed twice.
- Developers & analysts — strip repeated lines from logs, IDs, and CSV exports.
- Teachers & students — tidy up word lists and survey responses.
Prefer a spreadsheet? Compare Excel vs this online tool. New to deduping? Read the step-by-step guide.
Frequently asked questions
Does it keep the first or the last occurrence? By default the first. Switch to keep-last mode if a later entry should win.
Is my text uploaded? No. Processing is 100% local in your browser.
Does Apple count as a duplicate of apple? Only with Ignore case enabled. Otherwise they are different lines.
How large a list can it handle? Tens of thousands of lines process instantly.